In future years, 2010 may be remembered as the landmark year healthcare was finally secured for all Americans. It may be remembered for the most sweeping reforms of Wall Street ever. It may even be remembered for sweeping Democratic losses in congress.

Democrats have found it hard to temper their public delight at the hickjacking of their opponents' candidates, making the calculus that it will temper their impending disaster at the November elections. That's possible, but unlikely. The house of representatives is all but gone. The senate remains in Democrats' tenuous grasp.

But take the slightly bigger picture. If Republicans make the gains they're likely to, we're looking at two years of gridlock that can only benefit the president who will do what he does best – play mediator, speak with a voice of reason and be a calming influence in the polarised and chaotic Washington of the next two years. This, combined with the Palin factor – forcing primary Republican presidential challengers to veer violently to the right – will improve Obama's chances of re-election in 2012.

Yet, this still misses the greater point.

The Republican "tent" is straining: witness the cannibalism already taking place this weekend, with Karl Rove attacking the tea partiers, with moderate senator Lisa Murkowski of Alaska announcing a "write-in" campaign against her extremist opponent Joe Miller (the guy that says unemployment benefits are unconsititutional).

The Republican party is already already severely divided. And this isn't temporary. On one side, the nationally electable socially moderate (and fiscally conservative) candidates like Mitt Romney. On the other side, Sarah Palin and associates. Enough said. Remonstrations are already rife in the party. Expect that to accelerate.

As America – admittedly, slowly – becomes more socially moderate (see polls on greater acceptance of gay rights, belief in healthcare, etc), Republican leaders in Washington are doing their best to portray an inclusive party. Many in the Republican camp are on board with the moderate strategy (see Ken Mehlman – Bush's chief strategist's – call for acceptance of gay rights, or Karl Rove's repudiation of the Tea Party).

It's tempting to compare the Republican party to the British Conversative party of the late 1990s: at war with itself; unsure of its identity; fundamentally torn by the issue of Europe and forced into being the party of "no" (remember William Hague's "Five days left to save the pound" campaign?). The answer for the Conservatives was to modernise, tack to the middle and embrace social change. They were able to do so not least because of the ageing population of the most rightwing elements.

Americans Republicans don't have that luxury. Tea Partiers aren't dying out. Their extremism is sustained, in part, by thriving Christian fundamentalism. They're here to stay. And they're here to be vocal.

And so the inevitable conclusion? A Republican party that either is doomed to represent an extremist vocal minority, or – more likely – a schism in the party. It's doubtful that will take place anytime soon. It will take a series of disasters to prompt change. But the cracks in the party are widening. They will become chasms, especially as the country moves on.

So, this November, when Democrats inevitably despair, most will miss the long-term point. Forget a structural Republican majority. Instead, prepare for a long, drawn-out, ugly and very public destruction of the Republican coalition. You think this weekend has been bad; just wait. This isn't a matter of if; the Tea Party, or whatever it morphs into, is here to stay.

What will happen? That depends on timing, election results and the inevitable advance of moderate political views in the nation. But we should be clear about one thing. Twenty years from now, hopefully earlier, American politics will be unrecognisable. Yes, there will be an ugly fringe, probably forever. But ultimately, this will be a system that celebrates moderate views and progress. And it's just possible we will see a three-party system (already, the desire of 60% of American voters) as Democrats and moderate Republicans recognise the need to appeal to this majority of voters, not the vocal minority of activists.

So, sure, brace yourself for an ugly election. And an ugly two years. But take the long-term view. The longer the Tea Party thrives, the better it is for moderates in American politics.